Dam Safety Improvements
(Royal Lake, Woodglen Lake and Lake Barton)
Updated: March 2008
Royal Lake
Royal Lake Question and
Answer
Royal Lake
Presentation
Information
Sheet #1
Information
Sheet #2
Recently, Supervisor Bulova hosted a Pardon Our Dust meeting in
anticipation of the construction set to begin at Royal Lake.
Here is some information that you might find helpful as construction
begins!
In addition to the plans for Royal Lake, there are also two other
lakes being studied for future work: Woodglen Lake and Lake
Barton.
The Woodglen Lake dam
(constructed in 1981) and Lake
Barton dam (constructed in 1978) are both located in the Braddock
District. These dams were built to capture sediment and to prevent it
from moving downstream. Today, neither lake meets today's design and
safety criteria. While the chance for a structural failure is very
remote, studies have shown that some residents and roadways would be at
risk should there be a catastrophic failure of the dam. For this
reason, the Virginia Department of Conservation and Recreation has
issued a conditional operations certificate to the Fairfax County Board
of Supervisors with the provision that the deficiencies must be
addressed.
Woodglen Lake
The comment period for the watershed plan for the rehabilitation of Lake Barton has passed. Please watch this page for further updates re: the signing ceremony and construction information.
Lake Barton
The hydrologic and hydraulic (H&H) studies for Lake Barton have
been completed and NRCS is in the process of developing draft planning
documents using the results.
As part of the H&H study, a sediment survey
was completed to estimate the sediment pool capacity. At the current
time, the sediment pool has a projected life of 42 years. NRCS
considered two alternatives for increasing sediment pool capacity to
the minimum required 50 years: (i) raising the permanent pool
elevation, and (ii) dredging. The preferred alternative is to raise the
permanent pool 0.8 feet. This will have minimal impact on the
recreational area around the lake and is considered to be the most
cost-effective option. The H&H analysis showed that the permanent
pool could be raised to this level without having to raise the
auxiliary spillway crest which means that there would no impact on the
existing floodplain. The preferred spillway rehabilitation option is to
line the existing spillway with articulated concrete blocks and extend
the spillway downstream. A conceptual layout was prepared as part of
the H&H study, but the proposed alignment may be revised as the
concept design is developed further. As part of the preliminary design,
a number of options for construction access will be developed. It will
be the County's preference to develop a permanent access road for
future maintenance activities.
Keep watching this site for future updates!